1. Technical Field
The present invention relates generally to a time and space-deterministic task scheduling apparatus and method using a multi-dimensional scheme and, more particularly, to a time and space-deterministic task scheduling apparatus and method using a multi-dimensional scheme, wherein tasks are scheduled in real time by ensuring that time and space complexity is always 0(1) regardless of the extension of priorities in a system having considerably limited hardware resources, such as, a wearable personal computer (PC).
2. Description of the Related Art
A wearable PC is a computer having a PC function contained within clothing.
More specifically, a wearable PC started to be developed for U.S. military training, and the application range of wearable PCs has gradually expanded to fashions, mobile communication devices and digital products in addition to daily life applications. A wearable PC is a future computing technology that may be successfully achieved only when it is researched in close association with several fields, such as mechanics, physics, textiles (e.g., advanced materials, designs, and fashions), ergonomics and psychology, in addition to a computer technology. “Smart clothing,” that is, a new type of next-generation clothing in which various types of digital devices and functions for future daily life are integrated into clothes, also has many things in common with a wearable computer.
In order to support various services required by users as in a conventional PC, a real-time operating system (OS) capable of predicting the execution times of respective kernel services needs to be used in a wearable PC in order to overcome an increase in the complexity of applications installed on a system and the limitation of hardware resources, such as the structural CPU performance of a wearable PC, the capacity of memory and the capacity of a battery, and to guarantee a user's quality of service (QoS).
A real-time OS needs to be configured such that the deadlines of all real-time tasks are satisfied and a priority reversal phenomenon in which a task having a low priority occupies a CPU when a task having a high priority in an execution preparation state is present is prevented to ensure time determinism. For this purpose, a real-time OS requires a task scheduling algorithm that ensures time determinism regardless of priority, but a conventional algorithm experiences memory overhead attributable to the extension of priorities.
Accordingly, there is a need for a time and space-deterministic task scheduling apparatus and method using a multi-dimensional scheme, which schedule tasks in real time by ensuring that time and space complexity is always 0(1) regardless of the extension of priorities in a system having considerably limited hardware resources, such as a wearable PC. Korean Patent Application Publication No. 10-2000-0037391 discloses a related technology.